22's 1980 xs650 build thread

The primary concern would be the wire circled between there and the fuse box. After that point, theoretically (and practically) a short-circuit should pop the fuse. Unhook it there, put a meter on it, shake it, pull on it, push on it, while checking continuity to ground. Check it thoroughly where it enters the fuse box too. I reckon Yamaha put extra shielding on it for a reason.
I checked that wire and specifically where you have circled, it's double if not triple insulated, the rest of it seems to check out as well but I'll take a second look with some daylight. I attached a pic of the top as well, don't believe there's any concerns there either.
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I'm running two Deka AGM batteries right. Both are at least seven years old. Deka is make in Pennsylvania. I've had several of them and no issues. If they cost more, I don't care. My bikes are an XS650 and XS1100. Both have solid state regulator-rectifiers. Both electrical systems are stock and maintained as well as I am able. I have no battery issue, even if both drop dead today.

I suspect there are a lot of 2nd rate batteries on the market and failures are not uncommon. I used to run flooded wet cell batteries in my 650 Special and they lasted a couple years, maybe. I suspect vibration took them out. I think I've been running AGM batteries for over 20 years now. The first one came from Mike's XS when Mike Lalonde had the business and that battery lasted nine years!

This was a fairly cheap battery, Parts Unlimited brand, however I am a believer in good batteries so instead of buying the Parts Unlimited battery for $80, I splurged for the $140 Yuasa this time. I'm thinking this is a faulty battery issue, I brought the battery inside over the winter, it sat for probably 3-4 months, I charged it and it went full almost right away, I let it sit for another month or two, put it on the charger and thats when it took hours and hours to get full which was way different than the first time. Yesterday was only my 2nd and 3rd rides of the season so maybe it took till ride 3 to call it quits? About 200kms.
 
The primary concern would be the wire circled between there and the fuse box. After that point, theoretically (and practically) a short-circuit should pop the fuse. Unhook it there, put a meter on it, shake it, pull on it, push on it, while checking continuity to ground. Check it thoroughly where it enters the fuse box too. I reckon Yamaha put extra shielding on it for a reason.
Oh wait, I completely forgot, when I was disconnecting the battery after cranking it over a bit the positive terminal felt warm or almost hot, does this mean there is a short somewhere? I can't confirm that it was hot 100% but I'm pretty sure.
 
Your wiring looks really good. My previously stated concerns were based on the all-too-typical shoddy condition of most older bikes' wiring and the rapid developing nature of your problem. I'm confident you're right.

The XS starter draws a lot of amps, any amount of cranking will produce some heat.
 
New battery should be here tomorrow and the old battery is still under warranty, literally for another 7 days, usually your part breaks just after the warranty expires.... this time I guess I got lucky. Really hoping the issue was a defective battery.

Next up on my to do list is probably either rebuilding or replacing the petcock. It leaks just a bit, not to the point of actually dripping but one of the fiber washers is always wet and the back part of the petcock always seems to collect dirt as if it's a bit damp or something. Anyways I'm at the point where I'm trying to decide whether I should get a rebuild kit, buy specific parts, buy a new vacuum petcock or buy a new manual petcock. Seems like vacuum vs manual is really personal preference but is it worth it for me to try rebuilding it first? Either with a kit or buying individual parts, any thoughts or opinions would be great.
 
I decided to try a new manual petcock and will maybe try rebuilding the vacuum petcock over winter or something. Anyways when I try to use the 90° outlet it points to like 6 o'clock, is there a trick to getting it to point to say 3, 4 or 5 o'clock? I've tried all the washers for a slightly different fit buy they're all the same or worse. 6 o'clock can work if need be but I might as well use the straight outlet at that point, any tips???

I also read that people have had issues with the filters coming off, I found that I was able to push them on a bit further than how they came, I was actually able to push the filter for the taller pipe down quite a bit so about a third of the filter is on the pipe, hoping this helps keep them on.
 
I was hoping genuine mikuni mains would cure my flat spot in the 4-6k rpm range and it seemed like it did the first couple times out but yesterday the flat spot was definitely there. 1.5" headers with commando mufflers, stock everything else. Right now the only carb adjustment has been to go to a 135 main, should I move up to a 137.5 or should I adjust the needle? Right now the needle is stock in the center position. I'd like to get this right the first time so I don't need to rip them off again. My understanding is that I should start by upping the mains but I'm also wondering if maybe the needle adjustment makes more sense here because it's just a small flat spot for about a second.
 
I was hoping genuine mikuni mains would cure my flat spot in the 4-6k rpm range and it seemed like it did the first couple times out but yesterday the flat spot was definitely there. 1.5" headers with commando mufflers, stock everything else. Right now the only carb adjustment has been to go to a 135 main, should I move up to a 137.5 or should I adjust the needle? Right now the needle is stock in the center position. I'd like to get this right the first time so I don't need to rip them off again. My understanding is that I should start by upping the mains but I'm also wondering if maybe the needle adjustment makes more sense here because it's just a small flat spot for about a second.
My ‘83 (stock pipes, stock air box) was running just fine on stock jetting. Somehow, I convinced myself it was too lean. I went up one size on the pilot and one on the main. Seat of the pants, it runs just the same, no difference. Fuel economy went from 56 to 49 mpg and the plugs got more color. To skew this, I dropped from a 34 to a 33 tooth sprocket. I expect I’ll be putting everything back the way it was.

I think you should try needle adjustments before making jetting changes. JMHO
 
Is this a "fixxed" needle arrangement? Just saw your post, apparently not. Good. I think you can get at mains through the floatbowl drain. If not, draining the float bowls and removing them is still easier than pulling the carbs.
 
Is this a "fixxed" needle arrangement? Just saw your post, apparently not. Good. I think you can get at mains through the floatbowl drain. If not, draining the float bowls and removing them is still easier than pulling the carbs.
Correct, It's a Canadian bike with the Canadian needle and the 5 clip positions. Currently in #3 I'll move it to #4. If that doesn't help I'll up the main one size. Haven't tried doing it with the carbs in place but it sure would be nice to do it that way.
 
Correct, It's a Canadian bike with the Canadian needle and the 5 clip positions. Currently in #3 I'll move it to #4. If that doesn't help I'll up the main one size. Haven't tried doing it with the carbs in place but it sure would be nice to do it that way.
One of the denizens here walked me through it in "New to me XS650". I will find it
 
Thanks for that, definitely helpful and I'll attempt to change the mains with the carbs on the bike because it looks like I'll need to. I moved the clip down 1 to a lot #4 and it seemed to fix the flat spot a bit but it was still there so I think I'll up the mains to 137.5 and put the clip back to slot #3. However, I'm starting to doubt whether it's a flat spot or bogging.

A bit windy but pretty nice ride today.
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Do you recall what size the stock mains were (130 or 132.5)? If they were 132.5's, one up to a #135 makes a totally stock bike run better so with any modding, 2 up will probably be needed.
 
Do you recall what size the stock mains were (130 or 132.5)? If they were 132.5's, one up to a #135 makes a totally stock bike run better so with any modding, 2 up will probably be needed.
Stock was 132.5, I'll go to 137.5 and back to slot 3 on the needle. The spark plugs are quite a bit darker after today's ride, I'd say almost too rich and yet I'm about to up the main jet.
...and going 2 up you might need your needle 1 notch lean from stock...
Maybe I will need to go up to slot 2 on the needle if I up the main jet to 137.5??
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Maybe. Needle slot position has a big effect on plug color. You're "tuning" the midrange with the needle and that's where you spend most of your time running, so it makes sense that it will really influence the plug color.

Normally, on the older BS38 carbs that aren't as pollution mandated (lean), the usual routine is to start increasing the mains one size at a time until you start getting break-up in the upper midrange under heavy or full throttle applications. Then you lean the needles a step to correct that. Now, you can go up another size on the mains but that usually brings the stumbling right back. So, once you start getting the stumbling, that's a pretty good indication that you've reached the max on main jet size. On my '83 with U.S. spec BS34 carbs (fixed needle), that happened with a 140 main, so I dropped back down to the 137.5's I had been running and called it good.
 
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